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OBSTACLES
Make sure that no in-flow path or objects
(e.g. cooling pipes, ladders, bracing
members, thermometers, etc.) or no tank
wall of the ragged surface protrude into
the sensing cone of the ultrasonic beam.
One fix object in the tank / silo that
disturb the measurement can be blocked
out by the appropriate programming of
the
DMSP400 and 500
.
STAND-OFF PIPE
The structure of the stand off pipe should be rigid; the inner rim where the ultrasonic beam
leaves the pipe should be rounded.
L
Ø D
r
L
Dmin
DMSP***A/C
DMSP***B/N
DMSP***D/E
150
50
60
60
200
50
60
75
250
65
65
90
300
80
75
105
350
95
85
120
FOAM
Foaming of the liquid surface may render ultrasonic level
metering impossible. If possible, a location should be found,
where foaming is the least (device should be located as far as
possible from liquid inflow) or a stilling pipe or well should be
used.
r
Ø D
L
L
Dmin
DMSP***F/G
DMSP***J/K/L/M
DMSP***P/Q
90
80
*
*
200
80
*
*
350
85
*
*
500
90
*
*
*
For values contact your distributor
WIND
Intensive air (gas) movements in the vicinity of the ultrasonic
cone is to be avoided. A strong draft of wind may
"
blow away
"
the ultrasound.
Devices with lower measuring frequency (40, 20 kHz) are
recommended.
FUMES / VAPOURS
For closed tanks containing chemicals or other liquids, which creates fume / gases above the
liquid
surface
especially
for
outdoor
tanks
exposed
to
the
sun,
a strong reduction of the nominal measuring range of the ultrasonic device is to be
considered during device selection.
Devices with lower measuring frequency (40, 20 kHz) are recommended in these cases
units.
